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<TITLE>[Chapter 23] 23.9 java.beans.Introspector (JDK 1.1)</TITLE>
<META NAME="author" CONTENT="David Flanagan">
<META NAME="date" CONTENT="Thu Jul 31 16:18:31 1997">
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<h2 CLASS=sect1><A CLASS="TITLE" NAME="JNUT2-CH-23-SECT-9">23.9 java.beans.Introspector (JDK 1.1)</A></h2>

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<P CLASS=para>
The <tt CLASS=literal>Introspector</tt> is a class that is never
instantiated.  Its static <tt CLASS=literal>getBeanInfo()</tt> methods
provide a way to obtain information about a Java bean, and
are typically only invoked by application builders or
similar tools.  <tt CLASS=literal>getBeanInfo()</tt> first looks for a
<tt CLASS=literal>BeanInfo</tt> class for the specified Java bean class.
For a class named <tt CLASS=literal>x</tt>, it looks for a <tt CLASS=literal>BeanInfo</tt>
class named <tt CLASS=literal>x</tt><tt CLASS=literal>BeanInfo</tt>, first in the current
package, and then in each of the packages in the
<tt CLASS=literal>BeanInfo</tt> search path.

<P CLASS=para>
If no <tt CLASS=literal>BeanInfo</tt> class is found, or if the
<tt CLASS=literal>BeanInfo</tt> class found does not provide complete
information about the bean properties, events, and methods,
<tt CLASS=literal>getBeanInfo()</tt> "introspects" on the bean
class by using the <tt CLASS=literal>java.lang.reflect</tt> package to fill
in the missing information.  When explicit information is
provided by a <tt CLASS=literal>BeanInfo</tt> class, <tt CLASS=literal>getBeanInfo()</tt>
treats it as definitive.  When determining information
through introspection, however, it examines each of the
bean's superclasses in turn, looking for a <tt CLASS=literal>BeanInfo</tt>
class at that level or using introspection.  When calling
<tt CLASS=literal>getBeanInfo()</tt>, you may optionally specify a second
class argument that specifies a superclass for which, and
above which, <tt CLASS=literal>getBeanInfo()</tt> does not introspect.

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<PRE>
public class <tt CLASS=literal>Introspector</tt> extends Object {
    // <tt CLASS=literal>No Constructor</tt>
    // <tt CLASS=literal>Class Methods</tt>
            public static String <tt CLASS=literal>decapitalize</tt>(String <tt CLASS=literal>name</tt>);
            public static BeanInfo <tt CLASS=literal>getBeanInfo</tt>(Class <tt CLASS=literal>beanClass</tt>) throws IntrospectionException;
            public static BeanInfo <tt CLASS=literal>getBeanInfo</tt>(Class <tt CLASS=literal>beanClass</tt>, Class <tt CLASS=literal>stopClass</tt>) throws IntrospectionException;
            public static String[] <tt CLASS=literal>getBeanInfoSearchPath</tt>();
            public static void <tt CLASS=literal>setBeanInfoSearchPath</tt>(String[] <tt CLASS=literal>path</tt>);
}
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